mxw01-thermal-printer

Framework-agnostic library for MXW01 thermal printer with support for browsers, Node.js, Bun, and more.

Features

• 🎯 Framework-agnostic - Pure TypeScript core, works everywhere
• 🌐 Multi-platform - Browsers (Web Bluetooth), Node.js, Bun
• 📦 Zero framework dependencies - Use with React, Vue, Svelte, or vanilla JS
• 🖨️ Advanced image processing - Multiple dithering algorithms (Floyd-Steinberg, Bayer, Atkinson, etc.)
• 🔌 Extensible adapters - Web Bluetooth, Noble (Node.js), custom adapters
• 🔄 Event-driven - Subscribe to printer events
• 📘 Full TypeScript - Complete type safety
• 📚 Examples included - React, Vue, Node/Bun implementations provided

Installation

npm install mxw01-thermal-printer

Optional Dependencies

For Node.js/Bun (Bluetooth):

npm install @stoprocent/noble

For Node.js/Bun (Canvas):

npm install canvas

For Node.js/Bun (Fabric):

npm install fabric

Quick Start

Browser (Vanilla JavaScript)

import { ThermalPrinterClient, WebBluetoothAdapter } from 'mxw01-thermal-printer';

// Create client
const adapter = new WebBluetoothAdapter();
const printer = new ThermalPrinterClient(adapter);

// Connect
await printer.connect();

// Print from canvas
const canvas = document.getElementById('myCanvas');
const ctx = canvas.getContext('2d');
const imageData = ctx.getImageData(0, 0, canvas.width, canvas.height);

await printer.print(imageData, {
  dither: 'steinberg',
  brightness: 128,
  intensity: 93
});

// Disconnect
await printer.disconnect();

Node.js / Bun

import { ThermalPrinterClient, NodeBluetoothAdapter } from 'mxw01-thermal-printer';
import { createCanvas } from 'canvas';

// Create client
const adapter = new NodeBluetoothAdapter();
const printer = new ThermalPrinterClient(adapter);

// Connect
await printer.connect();

// Create image
const canvas = createCanvas(384, 200);
const ctx = canvas.getContext('2d');
ctx.fillStyle = 'white';
ctx.fillRect(0, 0, 384, 200);
ctx.fillStyle = 'black';
ctx.font = '30px Arial';
ctx.fillText('Hello from Node.js!', 20, 100);

const imageData = ctx.getImageData(0, 0, canvas.width, canvas.height);

// Print
await printer.print(imageData);

// Disconnect
await printer.disconnect();

Framework Integration

The library provides a framework-agnostic core that can be easily integrated with any framework. Example implementations are included in the examples/ directory:

React Hook Example

See examples/react-hook.tsx for a complete React hook implementation.

import { useThermalPrinter } from './examples/react-hook';
import { useRef, useEffect } from 'react';

function App() {
  const canvasRef = useRef<HTMLCanvasElement>(null);
  const { isConnected, connectPrinter, printCanvas } = useThermalPrinter();
  
  // Draw on canvas when component mounts
  useEffect(() => {
    const canvas = canvasRef.current;
    if (!canvas) return;
    
    const ctx = canvas.getContext('2d');
    if (!ctx) return;
    
    // White background
    ctx.fillStyle = 'white';
    ctx.fillRect(0, 0, 384, 200);
    
    // Black text
    ctx.fillStyle = 'black';
    ctx.font = '30px Arial';
    ctx.fillText('Hello from React!', 20, 100);
    
    // Draw a rectangle
    ctx.strokeStyle = 'black';
    ctx.lineWidth = 2;
    ctx.strokeRect(10, 10, 364, 180);
  }, []);
  
  const handlePrint = async () => {
    if (canvasRef.current) {
      await printCanvas(canvasRef.current);
    }
  };
  
  return (
    <div>
      <canvas 
        ref={canvasRef} 
        width={384} 
        height={200}
        style={{ border: '1px solid #ccc' }}
      />
      <div>
        <button onClick={connectPrinter} disabled={isConnected}>
          Connect
        </button>
        <button onClick={handlePrint} disabled={!isConnected}>
          Print
        </button>
      </div>
    </div>
  );
}

Vue 3 Composable Example

See examples/vue-composable.ts for a complete Vue composable implementation.

<script setup lang="ts">
import { useThermalPrinter } from './examples/vue-composable';
import { ref, onMounted } from 'vue';

const canvasRef = ref<HTMLCanvasElement | null>(null);
const { isConnected, connectPrinter, printCanvas } = useThermalPrinter();

// Draw on canvas when component mounts
onMounted(() => {
  const canvas = canvasRef.value;
  if (!canvas) return;
  
  const ctx = canvas.getContext('2d');
  if (!ctx) return;
  
  // White background
  ctx.fillStyle = 'white';
  ctx.fillRect(0, 0, 384, 200);
  
  // Black text
  ctx.fillStyle = 'black';
  ctx.font = '30px Arial';
  ctx.fillText('Hello from Vue!', 20, 100);
  
  // Draw a rectangle
  ctx.strokeStyle = 'black';
  ctx.lineWidth = 2;
  ctx.strokeRect(10, 10, 364, 180);
});

const handlePrint = async () => {
  if (canvasRef.value) {
    await printCanvas(canvasRef.value);
  }
};
</script>

<template>
  <div>
    <canvas 
      ref="canvasRef" 
      width="384" 
      height="200"
      style="border: 1px solid #ccc;"
    />
    <div>
      <button @click="connectPrinter" :disabled="isConnected">
        Connect
      </button>
      <button @click="handlePrint" :disabled="!isConnected">
        Print
      </button>
    </div>
  </div>
</template>

Core API

ThermalPrinterClient

The main client class for interacting with the printer.

import { ThermalPrinterClient, WebBluetoothAdapter } from 'mxw01-thermal-printer';

const adapter = new WebBluetoothAdapter();
const printer = new ThermalPrinterClient(adapter);

Methods

• connect(): Promise<void> - Connect to the printer
• disconnect(): Promise<void> - Disconnect from the printer
• print(imageData: ImageData, options?: PrintOptions): Promise<void> - Print an image
• getStatus(): Promise<PrinterState | null> - Get printer status
• setDitherMethod(method: DitherMethod): void - Set dithering algorithm
• setPrintIntensity(intensity: number): void - Set print intensity (0-255)
• on(eventType, listener): () => void - Subscribe to events
• dispose(): void - Clean up resources

Properties

• isConnected: boolean - Connection status
• isPrinting: boolean - Printing status
• printerState: PrinterState | null - Current printer state
• statusMessage: string - Current status message
• ditherMethod: DitherMethod - Current dithering method
• printIntensity: number - Current print intensity

Events

printer.on('connected', (event) => {
  console.log('Connected to:', event.device.name);
});

printer.on('disconnected', () => {
  console.log('Disconnected');
});

printer.on('stateChange', (event) => {
  console.log('Printer state:', event.state);
});

printer.on('error', (event) => {
  console.error('Error:', event.error);
});

Configuration

Print Options

interface PrintOptions {
  dither?: DitherMethod;           // Dithering algorithm
  rotate?: 0 | 90 | 180 | 270;    // Rotation angle
  flip?: 'none' | 'h' | 'v' | 'both'; // Flip direction
  brightness?: number;              // Image brightness (0-255, default: 128)
  intensity?: number;               // Print intensity (0-255, default: 93)
}

Dithering Methods

| Method | Best For | Description | | ------------ | --------------------- | ------------------------------ | | threshold | Text, simple graphics | Basic black/white conversion | | steinberg | Photos, general use | Floyd-Steinberg (recommended) | | bayer | Patterns, textures | Ordered dithering | | atkinson | Comics, illustrations | Atkinson dithering | | pattern | Special effects | Pattern-based dithering |

Understanding Parameters

brightness - Image Pre-processing

• Range: 0-255 (default: 128)
• Effect: Adjusts image lightness before printing
  • Lower values (0-127): Darker image (more black pixels)
  • 128: Normal (recommended)
  • Higher values (129-255): Lighter image (fewer black pixels)

intensity - Print Head Heat

• Range: 0-255 (default: 93)
• Effect: Controls thermal print head temperature
  • 50-80: Light printing
  • 80-100: Normal printing (recommended)
  • 100-150: Dark printing
  • 150-255: Very dark (risk of paper damage)

Recommended Settings

| Use Case | brightness | intensity | Description | | ----------- | ---------- | --------- | ------------------ | | Normal text | 128 | 93 | Balanced, readable | | Photos | 140 | 100 | Good contrast | | Barcodes/QR | 128 | 110 | High contrast | | Light draft | 150 | 70 | Saves heat | | Dark/bold | 110 | 120 | Maximum darkness |

Examples

Complete working examples are provided in the examples/ directory:

• nodejs-canvas-example.ts - Basic Node.js/Bun implementation
• nodejs-fabric-example.ts - Node.js/Bun with Fabric.js for advanced graphics
• react-hook.tsx - React hook implementation
• vue-composable.ts - Vue 3 composable implementation

These examples show how to integrate the core library with different frameworks. You can copy and adapt them to your project.

Platform Support

| Platform | Support | Adapter | Notes | | ------------ | ------- | ------------------------ | ---------------------------------- | | Browser | ✅ | WebBluetoothAdapter | Requires Web Bluetooth API | | Node.js | ✅ | NodeBluetoothAdapter | Requires @stoprocent/noble | | Bun | ✅ | NodeBluetoothAdapter | Same as Node.js |

Browser Compatibility

Web Bluetooth API is supported in:

• ✅ Chrome/Edge 56+
• ✅ Opera 43+
• ✅ Chrome for Android

Not supported in:

• ❌ Firefox
• ❌ Safari (as of 2024)

Architecture

┌─────────────────────────────────────┐
│      Framework Examples              │  ← React, Vue (examples/)
├─────────────────────────────────────┤
│    Platform-Agnostic Core            │  ← ThermalPrinterClient (src/core/)
├─────────────────────────────────────┤
│        Bluetooth Adapters            │  ← Web, Node.js adapters (src/adapters/)
├─────────────────────────────────────┤
│        Service Layer                 │  ← Protocol, image processing (src/services/)
└─────────────────────────────────────┘

The library is designed with clear separation of concerns:

• Core - Framework-agnostic client with event system
• Adapters - Platform-specific Bluetooth implementations
• Services - Printer protocol, image processing, dithering
• Examples - Reference implementations for different frameworks

Advanced Usage

Creating Custom Adapters

You can create custom Bluetooth adapters for other platforms:

import type { BluetoothAdapter } from 'mxw01-thermal-printer';

class MyCustomAdapter implements BluetoothAdapter {
  async isAvailable(): Promise<boolean> {
    // Check if Bluetooth is available
  }

  async requestDevice(): Promise<BluetoothDevice> {
    // Request device from user
  }

  async connect(device: BluetoothDevice): Promise<BluetoothConnection> {
    // Connect and return connection with characteristics
  }
}

// Use your custom adapter
const printer = new ThermalPrinterClient(new MyCustomAdapter());

Direct Protocol Access

For advanced use cases, you can use the low-level protocol directly:

import { MXW01Printer, prepareImageDataBuffer, encode1bppRow } from 'mxw01-thermal-printer';

// Create printer instance
const printer = new MXW01Printer(controlWrite, dataWrite);

// Set intensity
await printer.setIntensity(93);

// Request status
await printer.requestStatus();

// Print image
const imageBuffer = prepareImageDataBuffer(binaryRows);
await printer.printRequest(binaryRows.length, 0);
await printer.sendDataChunks(imageBuffer);
await printer.flushData();
await printer.waitForPrintComplete();

Troubleshooting

Connection Issues

• Ensure Bluetooth is enabled on your device
• Make sure the printer is charged and turned on
• Try disconnecting and reconnecting
• Check that no other application is connected to the printer

Print Quality Issues

• Adjust brightness and intensity settings
• Try different dithering algorithms
• Check that the thermal paper is properly loaded
• Clean the thermal print head if necessary

Node.js Issues

• Ensure @stoprocent/noble is properly installed
• On Linux, you may need to grant Bluetooth permissions
• On Windows, ensure Bluetooth drivers are up to date
• Check that no other Bluetooth service is using the adapter

TypeScript Support

The library is written in TypeScript and provides complete type definitions:

import type {
  ThermalPrinterClient,
  PrinterState,
  PrintOptions,
  DitherMethod,
  BluetoothAdapter,
  PrinterEvent
} from 'mxw01-thermal-printer';

Contributing

Contributions are welcome! Please feel free to submit issues and pull requests.

License

MIT

Credits

Based on the MXW01 thermal printer protocol. The identification of the protocol and its operation would not have been possible without dropalltables/catprinter.

Big thank you to the original researchers and contributors.

Author

Made with ❤️ by Clément Van Peuter